Constant-polarity holder for dry cells



g- 1942- A. MUNCHOW CONSTANT-POLARITY HOLDER FOR DRY CELLS Filed Aug.14. 1940 ji'aewr laid/71% J/Zuracfia w fi Km 22AM M QM. M5233 PatentedAug. 18, 1942 Leland A. Munchow, Madison, Wis., assignor to lgay-O-VacCompany, a corporation or Wiscon- 8 1 Application August 14, 1940,Serial No. 352,598

6 Claims.

This invention relates to terminal holders for dry cells wherein thepolarity of the current from the holder will not be changed even thoughthe cell is reversed in position.

The primary object of the invention is to provide a simple andinexpensive holder for a dry cell which is fool-proof as far asinsertion of the dry cells. is concerned. In many circuits, correctpolarity must be maintained, such as in hearing aids, radios, testequipment, cells in series or parallel, and the like. Frequently suchdevices are used b persons unfamiliar with electricity, and a cell isinstalled upside down to the damage of other cells and associatedequipment.

Another object of the invention is to provide a simple holder whereinthe proper polarity is obtained and the cell will be securely held inposition so that good connectionswill be maintained under severeconditions. For example, in hearing aid batteries it is important thatthe cell be firmly held, so that the resistance or the circuit will notchange while the battery is carried around, for such changes result inannoying noises in the apparatus.

The invention is illustrated in several embodiments in the accompanyingdrawing, in which- Figure 1 is a side elevational view of a holder foran interposed dry cell; Figure 2, an end elevational view or the same;Figure 3, a fragmentary sectional view, taken as indicated at line 3 ofFigure 2; Figure 4, a sectional view, taken as indicated at line 4 ofFigure 3; Figure 5, a side elevational view of the modified devicewherein one of the contact members is provided with integrally formedspring fingers to engage the body of the cell; Figure 6, a sectionalview, taken as indicated at line 6 of Figure Figure '7, anothermodification in which several dry cell holders are connected inparallel; and Figure 8, a diagrammatic view showing howa plurality ofdry cell holders may be connected in series.

In the embodiment illustrated in Figures 1-4, inclusive, an outerU-shaped contact 9 is arranged so that either of its arms is adapted tomake contact with the central electrode of a dry cell interposed betweensaid arms. The member is preferably made of resilient sheet metal suchas brass. A strip of insulating material in forms a lining for themember 9 and extends substantially throughout its inner length. It isprovided with cut-out portions II which form sockets to expose portionsof the member 9 and permit it to electrically engage the terminal I! ordry cell in contact with the member 9, at any time, by

- the insulating strip II.

inturned lips I'I which are adapted to engage only the bottom ll 01' thedry cell.

In the form shown in Figure 5, the central terminal I! of thedry cell isadapted to engage i3. The other terminal I4 01 the dry cell, which I isusually its bottom, is prevented from coming cell.

the contact 9 through perforations in the insulating strip III, asdescribed above. However, contact with the other electrode of thedrycell is made by means of resilient spring fingers it which areadapted to grip the exposed body of the cell. It will be understood thatin this form the usual cardboard cover of the dry cell must be removed.

In the formshown in Figure 7, the holders are connected in parallel bymeans of a connection i9 between the members 9. With this arrangement asingle resilient arm 20 serves as a contact for either of the holders.It will be understood that as many additional holders may be connectedin a. battery, in this manner, as may be desired. Also, it is notnecessary that the opposed contacts of the holder be integrally formed,as they may be made in separate contacting units secured to a suitablebase member.

Figure 8 illustrates diagrammatically how .many desired number ofholders may be connected in series by connecting member ii to the member9 of the next holder.

The foregoing detailed description has been given for cleamess ofunderstanding only, and no unnecessary limitations should be understoodtherefrom for some modifications will be obvious to those skilled in theart.

I claim:

1. A constant-polarity terminal holder for a dry cell comprising: a pairof heads oppositely disposed to engage either end of the dry cellinterchangeably, each of said heads having two contacts separated by aperforated strip of insulating material, the perforation in saidmaterial being adapted to receive loosely and center the exposed centralelectrode of a dry cell, one of said contacts having an exposedconducting area disposed in rear of one of said perforations so as toengage a central electrode inserted therethrough, and the other contacton the head disposed to engage only the bottom of the dry 2. A device asspecified in claim 1, in which the opposed pair or inner contactsengaging the bottom oi the cell are integrally formed, and'the outercontacts for engaging the central electrode are formed integrally from asingle strip of metal.

3. A constant-polarity terminal holder for a dry cell comprising: anouter U-shaped contact of resilient metal adapted at either end to en-Sage only the central electrode of an interposed dry cell; a strip ofinsulating material lining said outer contact and having cut-out socketportions exposing opposite areas of the arms of the contact and servingto position the central electrode of a cell when inserted therethrough;and an inner U-shaped contact of resilient metal having centrallydisposed short arms with contacting lips to engage. only the bottom ofsaid cell it presented thereto, said contacts being secured together inelectrically insulated spaced relation.

4. A constant-polarity terminal holder for a dry cell comprising: aU-sh-aped contact of recontact; and a second contact secured to saidinsulating strip and having arms adapted to engage an electricallyconductive outer wall of the cell when the first mentioned contact isconnected to said cell.

5. A device as specified in claim 4. in which the second contact hasarms disposed to engage an end wall of the cell beneath its center andopposite from the end of the cell engaged by the first mentionedcontact.

6. A device as specified in claim 4, in which the second contact hasarcuate fingers adapted :0 to engage and make electrical contact withthe side wall of the cell.

LELAND A. MUNCHOW.

